The present invention relates to an apparatus for producing molded articles such as seals, packings and the like.
There are numerous types of compression molding presses which utilize hydraulic rams to apply pressure to heated platens between which the molds are disposed. In a typical compression molding press, there are a plurality of spaced platens. The molds are disposed between the platens which in turn are heated either electrically or, more commonly, by means of steam or a liquid medium such as oil which is circulated through channels within the platens. Accordingly, the molding press utilizes the transfer of heat from the individually heated platens to the mold to effect curing of the article in the mold. Generally, such compression molding presses, such as for example the molding apparatus shown in U.S. Pat. No. 3,905,735, are open, or have the heat transfer bodies, e.g. the molds, open to the ambient resulting in significant losses of heat. Additionally, the heat being radiated from the presses necessitates the use of extensive cooling facilities in the area adjacent the presses to provide a suitable working environment for the operator of the press. Further, due to the fact that in many molding operations gases and vapors are given off from the material being molded during the curing, it is necessary to have hoods or other ventilation equipment disposed above the presses so that the operator is not exposed to the escaping gases and vapors.
Another problem associated with most prior art compression molding presses is that the space between the platens is fixed which necessitates that all molds placed between the platens be of the same height to avoid damage to the molds and/or the platens during the molding operation.